The invention relates generally to oil wells and, more specifically, to a system and method for controlling flow in a horizontal well production system.
Generally, pumping systems are used in a wide variety of environments, including wellbore applications for pumping production fluids, such as water or petroleum. The pumping systems typically include, among other components, a pump positioned at a sufficient depth such that fluids can be lifted to a surface without reliance on reservoir pressure alone. The function of the pump is to reduce a bottom hole pressure and increase a rate of production. The pump may be an electric submersible pump, a rod pump, a progressing cavity pump, or the like. Many of such wells deviate from a straight path in order to enter production zones and follow geological formations that are often within a narrow band. Further, these directionally drilled wells often extend vertically down to reach the depth of the production formation and then extend horizontally along the formation for production of natural gas and oil.
In such a well configuration, all produced liquids and gases must flow along a substantially horizontal portion of the well to reach a single pump intake location. When the produced liquids block the free flow of gas by filling the entire wellbore and forming a trap, the gas pressure builds up until the gas escapes past the trap and flows along a downstream direction of the well. The gas that escapes past the liquid blockage is often referred to as a “gas slug”, and is known to interfere with the operation of the pump, resulting in reduced production and damage to the pump. The increased wellbore pressure caused by buildup of the gas pressure results in further reduction in production flow rates. For a pumping system that includes a single intake passage, all production fluids migrate along the wellbore to reach the pump so that the production fluids can be lifted to the surface. Since most horizontal wells have many individual production zones distributed along the length of the well, production zones located closest to the pump intake, deliver fluids with less resistance to the pump. Production zones further away from the pump intake deliver fluids less effectively because of increased flow resistance between the production zone and the pump. Such drawbacks reduce the production rate and the total recovery of resources from the well.
There is a desire for a system and method for controlling flow in a well that allows increased production rates and total recovery.